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The Theory of Plate Tectonics



Vocabulary







plates - A section of the lithosphere that slowly moves over the athenosphere, carrying pieces of continental and oceanic crust.
scientific theory - A well-tested concept that explains a wide range of observations.
plate tectonics - The theory that pieces of Earth's lithosphere are in a constant motion, driven by convection currents in the mantle.
faults - A break in Earth's crust where slabs of rock slip past each other.
transform boundary - A plate boundary where two plates move/slip past each other in opposite directions.
divergent boundary - A plate boundary where two plates move away from each other.
convergent boundary - A plate boundary where two plates move towards each other.
rift valley - A deep valley that forms where two plates move apart.( A divergent boundary)


Outline


  • The theory of plate motion

    • Plate tectonics is the geological theory that states that that pieces of Earth's lithosphere on in a constant motion, driven by convection currents in the mantle.
      • plate can't budge without affecting the other plates surrounding it.
        • As the plates move, they collide , move, pull apart, or grind past each other, producing changes in Earth's surface.
          • These changes include:volcanos, mountain ranges, and deep-sea trenches.
  • Plate boundaries

    • There are three kinds of plate boundaries.
      • Transform boundary
        • A transforrm boundary is where two plates move past each other in opposite directions.
        • Earthquakes frequently occur along these boundaries.
      • Divergent boundary
        • A divergent boundary is where two plates move away from each other.
          • Divergent boundaries occur both in the water and on the land.



      • Convergent boundary
        • A convergent boundary is where two plates move towards each other.
          • There are 3 kinds of convergent boundaries
            • When continental crust and continental crust collides.
              • Big mountain ranges form.
            • When continental crust and oceanic crust collides.
              • The oceanic crust sinks
            • When oceanic crust and oceanic crust collides.
              • The plate that is denser sinks
  • The continents' slow dance

    • Plates move at slow rates.
      • From 1 to 10 cm. per year.
      • The North American plate and the Eukraisan plates are floating apart at a rate of 2.5 cm. per year.
        • That's about as fast as your fingernails grow.



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